The present invention relates to a microwave holograph device which can detect an object by scanning the microwaves.
Microwaves can be transmitted to a remote location via a free space and then reflected from a metal surface. However objects such as overcoats and handbags are transparent with respect to microwaves. For this reason microwaves can be used to detect flying objects and dangerous weapons disregarding other materials. In addition, the detected objects and weapons can be reproduced in a space by microwave holography.
A holographic image obtained by microwaves is first displayed on a CRT. An image on the CRT is then taken by photographic camera so as to form a holographic image, and then the holographic image is reproduced in a space by a light beam so that the reproduced image can easily be observed by an inspector.
The conventional image reproduction technique by means of the microwave holography, however, cannot be used to detect an image in real time because the holographic image obtained by the microwave technique must be converted into a photographic film image before the image reproduction.